Abstract:

A simulated experimental environment of small-step periodically-controlled climatic parameters, such as air velocity, temperature, humidity and heat radiation, is important to the repeated experiments of thermal performance for building envelope structures, and is effective in the investigation of passive evaporative cooling effect of porous materials in natural climate. This paper develops a dynamic laboratory of hot-humid climatic wind tunnel, in which the low-speed air flow is adjustable and the infrared light, the humidifier as well as the heating/cooling facility are set up, thus primarily implementing the simulation and control of such natural environmental elements as solar radiation, air velocity, temperature and humidity. The PC-based measurement and control system of the hot-humid climatic wind tunnel uses a data collector block to manage the data collection, the data feedback and the control instruction output. Thus, the environmental elements can be real-timely examined, numerically displayed and effectively saved. It is shown from special mechanism calibration that the control precisions of solar radiation, air velocity, temperature and humidity in the developed dynamic laboratory are respectively ±10 W/m²,±0.2 m/s, ±0.5℃ and ±5%.

Key words: wind tunnel, hot-humid climate, evaporative heat transfer, measurement and control system